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A project of Volunteers in Asja

Makina the Adobe Brick

by:

Eugene H. Boudreau

.

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,,Published by;

Fifth Street Press

1409 Fifth Street

Berkeley, CA 947.10 USA

' +

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5

'Y.

Paper copies aree$ 5.00.

Available from:

.s

META Publications

-

P.-O. Box 128

Marblemount,

WA 982fi7 USA

Copyright (c) 1971 by Eugene H. Boudreau."

Photographs by John Pearson._ Reproducied by

permission of Random House, Inc.

I

Reproduction OK-this microfiche document in any

form is-subject to the same .restrictions as those

I

_ 1 _

of the original document.

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THE

A.DOBE

BiUCK ‘B

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EUGENE iI. BOUDREAU

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’ FIFTH.

‘STREET

PRESS

‘5

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Copyright 0 1971 by Eugene H. Boudreau

All rights reserved

.

First printing, September 1971

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S&ond printing, October 1972

Third printing, May 1973

Fourth printing, March 1974

Cover design, Book design by Anne Kent Rush

,-

Photographs by John Pearson

Piinted and Bound by Murray Printing

Forge Village, Massachusetts.

Published by Fifth Street Press

-. 1409 Fifth Street ”

Berkeley; California 947 10

Fifth Street Press is an imprint of the Bookworks

Li,tary of Congress Catalog Card Number: 71-178955

ISBN# O-394-706 17-X

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istributed in the United States by Random House,.Inc.,

and incanada by Random House of Canada, Ltd.

,)

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.

L NTRODUCTION

MAKING THE ADOBE BRICK

Basic Components

Sand

Clay

Straw

-.

Stabilizer

Mel+

‘Testing the Soil

Testing the ?Tabilized Brick

Ma:king Adobes

Equipment Needed

Mixing & Casting

Drying & Curing

BUILDING? WITH ADOBE BRICK

Research & Design

The Foundation

Laying Adobe Bricks

Lintels, Bond Beam & Wal Plate

The Roof

Plumbing

Electric Wiring

Loose Ends

APPENblCES

Letter from a Friend

Uniform Building Code Requirements

Fireplace & Chimney Details

Engineering Calculations

Percolatjon Test Procedure

Disposal Field

Bibliography

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7

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13

17

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23

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39

41

47

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58 _

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63 "

69

71 ".

72

74 '

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* 86

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also by Eugene H. Boudreau

Buying Country Land

Trails of the Sierra Madre

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Q .To my bealtiful, vivacious and hard-working wife.

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The author%&Zo thankthe-followingsour,ces for permission

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to quote from their.rnaterialin-~h~‘~~~- ---“w

Sonoma County Public,Health Serv’ e for ,petjnis$on to

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:’ ’ ,reprint “Percolati

tf

Test Procedure”.

Sonoma Ckunty Buildinanspection Department for permission

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to reprint “Fireplace and,Chimney Deiails”.

,

International Conference of’Building Officials for permission

to reprint from THE UNIFORM BUILDING CODE

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STANDARD NO. 24+‘0 ;I

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INTRODUCTION a

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91

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.--The purpose of this book is to acquaint the reader with di the

information necessary to make adobe bricks that conform to the specifi-

cations o&the Uniform Building Code, and thus can be used for build-

ing a home or other structure.

My wife and I made 7,000 adobe bricks, totaling about 120 tons,

and then built a nine room house with them. ,Much of my knowledge

tias gained through trial and error as I had no previous experience in

this art, being a geologist by trade.

.

aI

Several persons have told me that they once had the intention of

making adobe bricks but that the lack of good information on the

.subject had kept them from ever getting started. If the reader has similar

ideas and is simil_arly frq

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c

S today’s newspapers will show that “adobe” is a prestige word;certifying

artistic uniqueness and premium quality in a house, and also a higher

price. Apart from homes built entirely of adobe, the existence of an

adobe fireplace or patio wall receives special mention, and I have even

seen a,stucco home revered as being “adobe colored”.

- -The fact that adobes do not require any complicated technology in

their manufacture and that structures made of them are pleasing to the

eye has not generated any great wave of increased use1 Partly this is be-

cause it is a lot of hard work, and partly because the adobe is not a part

of the average American’s heritage and thus the necessary knowledge

is not diffused throughout his awareness of what is possible. A big ob-

stacle to anyone trying to learn hoi;, to make; acceptable adobes is the

.; fact that little has been written on the subject, and most of that is out of

print. An even larger obstacle is that much of the literature, past and

present, that I have read is out of date, does not comply with the

specifications of the Uniform Building Code, and contains many omis-

sions of important information, some outright mi(sinformation, and too

much over-generalization.

-

The Uniform Building Code is a set of standards for construction

that has been adopted in many areas of the U. S. Any construction with

adobe in these areas must conform with the provisions in the Code that

v*

deal with adobe. Following the Code means safe and sound construction.

Of course there are man

adobe buildings in the world that are not

built according to the Code,

%

and every year earthquakes knock down

thousan

P

s of them. In these buildings, the adobe bricks are not water-

proofed; mud is, used for mortar, no reinforcing steel is used, and no bond

beam is poured along the fop of the wall. The traditional method of

protecting adobe walls against rain is with wide. roof eves and/or a

skin of mud plaster, with the plaster requiring periodic patching as it

‘erodes away. It follotis that the traditional method of building with

adobe is suitable only in arid or semiarid lands where there is no possi-

bility of earthquakes of any great magnitude.

This book began as a work limited to the subject of hoti to make

adobe bricks. Then, the publisher suggested that it would be helpful to

include a section on laying adobe bricks, as anyone wanting’ to make

adobes would undoubtedly want to build something with them. This

I could do, but the building of adobe walls involves knowing about such

things as foundations, electrical outlets, reinforcing steel, bond beams,

etc. --.

The solutionewas to.expand the book to tell something of how my

wife and I planned and built our adobe home, which will help the reader

by acquainting him with many of the things that enter into any type

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of adobe construction. Added to this are information sheets in the Ape

pendix and the names of reference sources which I found useful; some

of these may be obtained from local libraries or bookstores;

9

To my knowledge, building with adobe is the only way that a

fam.ily with no experience and little money can come to own a truely

fine home and not be deepiy iti debt when it’s finished. To this ca,n be

added the observation that it is a useful, viable, and highly appreciated

form of self-expression.

For a family to build an adobe home is a task of monumental pro-

R

portions. Although I have read that it should always be looked on as

“fun,” I found that the exigent attitude of “NO EXCUSES GET

MOVING NOW ” that was imbued in me during my days in the

Marine Corps was what got the work done. Then, of course, there ‘was

the lure of the Challenge. Further inspiration can-be derived from read-

ing such classics pas Victor, Hugo’s

Toilers.

of the,Sea, and Kipling’s

poem “If”.

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THE

ADOBE BRICK

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R

BASIC COMPONENTS . : _ c,

Adobe bricks consist mainly of a mixture of sand and clay to which;

L

” in order to conform with the requirements of the Uniform Building

,Code, a waterproofing substance is added. A good general way to

regard the sand and clay in an adobe is to liken t,hem to the components

A.

of concrete. In this comparison, the sand in the adobe fills the role of

the sand and gravel aggregate in concrete; in other words, it is an inert

y

filler. Clay in the adobe is the binder, as is the cement component in

concrete.

Even as the proportion of cement in‘concrete is less than that of

the aggregate, so a proper adobe brick mix usually -contains less clay than.

sand. This is true even though a popular misconception is that adobe

;

bricks must be made of high clay content “adobe” soil. Remember that

/’

when “adobe”. soil dries out under the summer sun it shrinks up and

develops numerous wide and deep cracks, an’effect not wanted in adobe

brie ks.

The Uniform Building Code states that the clay content of adobe

bricks must be greater than 25% and less th$n .45%. Too -much

cla

and the brick develops cracks as it dries; too.:little clay and the brie

will be too weak when it dries and will crumble easily.

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: 0 Sand = .

Not much can be said aGut this ex

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14

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Clay

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The term clay refers to an assemblage of mineral particles, most

‘of which are hydrated aluminum silicates, which are of such a smal l

.

size that they are less than 0.005 millimeters in diameter. This assem-

- - --- blage- is plastic when moist ;and hard when dried. The actual clay

\-

1

minerals are the hydrated-aluminum silicates and they are divided into

3 main groups; the kaolin group, the montmorillonite group, and the

illite group. These groups differ chemically from each‘other, and their

molecular arrangements, or crystal *etruct%res, are also different. Q

.’

c

The type of %crystal structure is the most important feature in a

clay mineral’s suitability for making -adobes. Kaolin group clays have

noneexpanding type crystal’structures, whiie .clays of the montmorillonite

and illite groups have expanding-type crystal structures. Clays with

sxpanding-type crystal structures will hydrate and thus expand con-

.

siderably in volume in the presence of water, with consequent excessive

shrinking and cracking a‘s they lose the excess water upon drying.

I

:

,From theabove it is clear that soils containing a high percentage of,

kaolin group minerals in the clay fraction are to be preferred for making

adobes.

,

l

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The chief reason for this is that even a high clay-content soil can

->be use&thout fear of excessive cracking and the result yri’ill be stronger

bricks. A hi h 1

c ay content of non-kaolin clays means that too much

sand ,must be added, which detracts from the strength of-Z-the-1 ricks.

--Y- ;Also; kaolin clays are not nearly as sticky as the others’and thus are

-

.

easier to handle.

I -

In’the mercury mining district of ,$ain Alto in the state of Zacatecas,

Mexico, I h

-L?

ave seen adobes made from high-kaolin clay soil used to

make-retorts for the distillation of mercury from cinnabar ore and these- ,

-

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adobes did n&crack or crumble from the 1,000 F. heat.:.I was told th&

moisture had little affect on new uncurecj adobes.

‘-,._(

._

Kaolin clays, - because of their desireable YFharacteristics,“$iie @idely

.’ .used in making ceramics, pipe, chinaware and fir&bricks.

Kaolin clays can be formed,by natural weathering of\l feldspar

minerals in granitic rocks or by hydrothermal alteration. The color of

I

pure kaolin is white. Information on the location of deposits of kaolin

clays or soilsRigh in such clays should be obtainable from loca?@ologists

_.*.

or geologists with -such government- offices as the California Division

m

of Mines and Geology. Sonoma County, California, where 5 live, has

.c 4 r

several +posits near Nunn Canyon.

,.

‘. The-above stress on the desireability of using kaolin clays does not

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available,+ it would pay you&-go to some trouble and expense to get

,them. Also, some potential adobe-makers. may have no soil of their own

to- use and will have to import it by the truckload to the manufacturing

site. -Again, a high sand content soil may need the addition of some clay.

,’

s

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l Straw,,

J : ,- -

My experience with using stra,$ in adobes is that it is absoluteJy

degree ‘of cracking in the brick, even

30-35 %. Straw does not give &dded

ke the brick dry and shrink as one

r of contraction dev@ps and major

raw into lengths of about. 4 inches

the blades of the paddles of your

e bale, for about $1.50. If possible,

15

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s that adobes’be stabilized to

with water they will absorb no’

eir weight. Emulsified asphalt

ere may be more than one variety of emulsified asphalt, but my

which I bought from a local

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oil dealer, and from a local road paving company. The’ cost depends on

._*

. the quantity purchased, but it cost me about 17 cents per-gallon.

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’ Emulsified asphalt consists of tiny, droplets,.of asphalt dispersed in’

‘,” ‘water. RSP is a brown, sticky liquid which sellers store in heated tanks

. I

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so that, the asphalt will not congeal and settle out. You should not let

$1-

your RS.1’ sit around too long because the more congealing and settling

PF

_ .---‘l the less effect ive the stabilizer. It helps on cool days to set 5 gallon cans

(, =.

-:

of it over-a small fire to heat it to makepouring and, mixing ‘with the cool

- _’

mud easier.and quicker. Heating the water used- in preparing the mud

* -C till also- help..On warm days, simply set the RSl in the sun.

,

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Emuls ified asphalt serves to waterproof adobes but it does not con-

‘-.

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tribute to their strength; in fact, superfluous amounts will weaken the

brick.

.

/

The thought .of’ adding asphalt to an adobe brick may cause the

.- reader to envision something that looks.and smells like tar, but. this is

not the case. I found that thekoutside color of. my- adobes turned

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“portant esthetic illusions in a person’s mind it might be helpful to re-

member that the ancient inhabitants of Sumer and Babylon mined

asphalt from naturally occuring deposits for use as a mortar to hold

their adobes together.

Portland cement can be added to soil to give a strong brick which

’ will not be damaged by water. These bricks -are not waterproof, as are

tho e properly made with emulsified asphalt7 and so do not meet the’

?

re

4

uirements of the Uniform Building Code. However, because‘of their

gr ater

7

hardness they would serve well for porch floors and garden

walks. ‘Use about 15% cement and keep the bricks damp for a’ few days ‘.

so the cement will cure properly.

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MOLDS

CY

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A mold can be nothing more than 4 boards tacked together with a

couple of handles added, but there are refinements which can be in-

corpora&d to achieve more uniformly shaped bricks and to prolong the

life of the mold.

.

Use Douglas fir lumber for the mold as it is strong and will hold

nails and wood screws much better than pine or redwood, The boards ..

should be of fine-grained, finished, lumber as a: ribby grain or a rough . -.

surface will not separate easily from the mud. Waterproofing the boards

is a good idea.

Adobes look’best when they come in large’sizes. The standard sizes

for adobes are: 4X71/2X16 inches, used in double courses with a 1 inch

mortar joint for the 16 inch wide bearing walls in solid wall construction

and also in the curtain walls of post and beam construction, and

4X12X18 inches: used in solid wall construchon for non-bearing walls.

(see Research and Design, page 00)

The length and width of the desired brick size should be used for -

the inside dimensions of the mold, but the depth of the mold should

probably be 4% inches to achieve a 4 inch thick dry adobe as there is

usually some slight slumping of the mud when’the mold is removed and

the brick ‘shrinks somewhat as it dries. If not compensated for in the __

depth dimension of the-mold, that 9’4 inch will add up to 4% inches;

equivalent to laying an extra ,course, in a normal height wall of 18

courses.

The mold will be strengthened if wood screws are used instead of

nails to fasten the sides together. Corner braces, sold in hardware stores,

give needed rigid ity to ‘the mold;. I used 2 of them, placed diagonally

from each other in opposite corners. These braces should be countersunk

6 *

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Ado be

Mold

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Corner brace

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Top View

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-Side View

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I so they do,not protrude’above- the rest of the mold. *

AfterrthemoB has been-filled~with. mud the excess is scra&d off

with a rectangular mason’s trowel, which causes the top of the mold to

wear down “and become noticeably swaybacked. This wear can be elim-

inated by tacking a thin strip of metal. along the top.

,

There is often trouble in keeping, the mud from clinging to the*

interior of the mold when it is lifted off;‘such clinging causes misshaping

and corners till pull off the wet brick. A w,ay to facilitate the separation

*of mud from mold is to line the inside of the mold with thin sheet metal.

Another.way is to make the bottom of the mold slightly wider than the

/

top, about 1_/16 inch on each side.

Double molds can be made but the divider piece should be of ‘2 inch

thick lumber. The reason for the 2 inch divider is that the slumping of

the sides of wet adobes will sometimes be as great as l/2 inch and thus

of pairs-of adobes will touch if only. 1 inch lumber is

left, for air circulation so that drying can take ,place.

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. Gravity

Separotbm

Soil Test

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21

‘ , ’ . ”

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TESTING THE SOIL

--

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.

A simple way to test a soil for .its suitability for making adobe

bricks is as follows:

1. With a sho

ve , remove any sod, leaf mold, or other high organic

1

material from a small part of the area you wish to test.

‘-

2. Dig a hole down as deep as you plan to go in your excavating

for soil and thoroughly mix what you have taken from the hole.. -This

m,..1

must be done because soils often have prof,ilesi or- horizontal layers, of

different composition, and.theiraverage is needed.

.

.-$- Take%‘handful of the soil and put it in a jar with some w:ter

-:---.-~- and shake until the soil turns to mud; then set the-jar down and’let the

.solids settle out until the water becomes clear.

l

1- 4.- Examine

th

e settled contents of the jar. Any small ‘pieces of

rock in the soil ,will be at the bottom; next will be the sand, *with the

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.coarsest on the bottom and grading upward into silt-size particles; upper-

4 ’

most in the column is the clay, distinguishable by the&ck of any vi-sable ,_ -~-

---

particles. If some of the clay is rubbed between the.fingers it will feel

like soap and no gritty particles can be felt.

5. Estimate the % of the column occupied by the clay and the %

occupied by the coarser s ize particles.

The Uniform Building Code re-

* quires that the amount of clay-size mater ial fall within the range of -

25-45s. , .’

Another method of determining the composition of the soil is to

z , -

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ave a screen test made by a commercial’ testing laboratory, which will

-. .

ost about $5. This will give the 76 of the total material which will pass

through a 200 mesh per inch screen and thus be classifiable as ‘clay size.

Afgseither of the above testing methods have shown that the soil

in question does not have ‘more or less claysize mater ial than the pre-

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22

scribed range, mix some of it into a stiff mud and make several full-size

bricks. The reason for making full size bricks for test purposes is that

some soils will react very different1.y in the drying process depending

upon the relative amount involved. The first test bricks that I made of

my soil were only 2X4X4 inches and showed no cracks when dry, but

my first full-size bricks-of the same soil resembled jigsaw puzzles when

dry.

Dry some of your test bricks inihe sun, but dry some of the others

in the shade to see which drying conditions they respond to best. Shade

can be provided by a piece of plywood set an inch or, two above the

bricks.

Excessive cracking can be checked by shading, or by adding more

I sand or straw: If they are going to appear, cracks show up on the firs t

(Iay or two.

If your so il tests out to be too high in either sand or clay content you

can obtain sand or high clay soil from a local building materials firm for

blend-g to correct whichever deficiency exists.

When the adobes pass the drying tests it is then time to make some

qwith emulsified asphalt to see how much of the stabilizer will be needed.

Before beginning production, it is.wise to have some tests made for com-

pressive strength, modulus of rupture, absorption, and moisture content

---------_ ~....b_y_-~.c_comm-~~.laboratary*Jt. takesseveral weeks in the sun to get the

moisture content of adobes down to the allowed maximum of 4.056, but

this can be hurried by using a warm oven‘with the door open- after the

adobes are firm enough to be handled.

Tyour county building permit office can recommend one.

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‘23

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TESTIFG THE STABILIZED

BRICK

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Experiments must be made to “determine the amount of. emulsified

8 *

asphalt needed to stabilize adobes made from the soil you have already

:

.@ted and f

manner:

6

nd suitable for use. This can be done in the following

1. Measure out 1 cubic foot of loose soil by filling a, box of 1 cubic

foot capacity.

/

2. Dump &his soil into a wheelbarrow and hoe in enough water to ’

)

m..ke a at@ mud.

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3.“Slowly add l/2 gallon o f emulsif ied asphalt to the mud while

_‘/?-- mixing thoroughly with your hoe, and continue to mix until the

,.

asphalt is no longer discernable. The figure of i/2 gallon per cubic

foot of soil is the ratio th& I’ve found to be satisfactory.

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4. Hand-shape the mud into bricks small enough to be of conven#. Hand-shape the mud into bricks small enough to be of conven#

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&nt size, say 2)(3X+‘in&a.nt size, say 2)(3X+‘in&a.

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.-&&&-$ebricks. -%.iTca;n use a’;warm-oven-t~-avoid the long wait-&&&-$ebricks. -%.iTca;n use a’;warm-oven-t~-avoid the long wait

nece$ary whegdrying in the sun.ece$ary whegdrying in the sun.

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6. Talc&+a-dry test

brick and immerse- it in water for several hours.

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-- Kthe brick is sufficien tly stabilized, *no softening ,till have oc-

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cufred, even onthe edges. If the test is unsatisfactory then repeat

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iyt,using. more emulsified asphalt. Even if the/test is satisfactory

I .

it should be ,repeated with the use of less,stabilizer to’see if less

Gill give the same

good results.

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7. qfter finding out the stabi~~~r~-.to.w6h. ratio you .can figure how ” ,

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-much..:@ add .per’ mixer load ,according to the capacity of your

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mixer-in+rbic

feet ‘of soil. /”

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24

It is best to use a little more stabilizer than the minimum found

necessary in the testing as conditions may change somewhat while you

are in production. I found that even a slight reduction below the mini-

mum resulted in a great lessening in the bricks’ resistance to water. And

give the stabilizer time enough to mix completely with the mud.

L

a

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25

MAKING ADOBES

-0 Equipment .Needed

1. Molds for the various-size adobes to be made. W

2. A pointed nose shovel for excavating soil and a square point

shovel for shoveling mud from flat surfaces.

3. A pick for hard ground.

4. A sturdy, high-sided wheelbarrow with a broad rubber tire.

‘,’

5. Containers for emulsified asphaltL ~~

6. -Trowels for removing excess mud from the molds.

7. A large washtub for washing the molds.

8. Gloves. I used the -thin type used%. y women to protect their

/

hands while dishwashing. They don’t last long, but they don’t interfere

with your movements.

9. Various buckets and a couple of large drums for water storage.

+

10. A mechanical mud mixer. I bough’t a used plaster mixer, run

by a gasoline engine, which could mi 2 cubic feet of mud at a time.

An adequate mixer must have paddles o f some sort which stir up the

mud and scrape it from the sides. Cement mixers do not serve the pur-

pose. Check with dealers in used machinery, or new if you have the

-money:The old method of mixing the mud in a pit ,with the feet will not

serve if emulsified asphalt is to be mixed in, for all that it is more

“ethnic”. .

11. ~$4ade up casting surfaces and shade providers, which are op-

tional. Adobes can be cast on level ground, but it is more convenient to

use such a surface as that provided by plywod or boards. A friend of

mine, Andy Johnson, gave me a truckload,, of long, superannuated

foundation forms. These were 20 inches wide, and made of 3/s inch ply+

wood backed by a framework of 2X4 lumber. They were excellent for,

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I

26

the purpose. I had to use more foundation forms as shade providers be-

cause the adobes required shade and because numerous squirrels came

to make their homes under the forms on which the adobes were cast

and the neighborhood’s dogs came to chase the squirrels across-the tows

of damp adobes.

0 Mixing and Casting

Your soil should be mixed and broken up ai it is excavated so that

the different profiles or layers, if there are more than one, are converted

to one essentially homogeneous mass. By wetting down the excavated soil

beforehand and covering it with a sheet of plastic the mixing process can

be speeded up. A lot of time can be wasted in waiting for stubborn hard

lumps of clay to break down ipto mud.

When measuring your cubic foot of soil for experimenting with the

emulsified asphalt you should have noted the number of shovelfuls it

took to fill the-‘box. Multiply shovelfuls per cubic foot by the capacity

_ of your mixer in cubic feet and shovel in this amount as you charge

the mixer.

‘1

When ready to mix mud, first sta’hthe mixer and add most of the

amount of water that you estimate will/be needed. Shovel in the soil

and then add just enough more water td make a stiff mud. Sloppy mud

is useless. Allow the paddles time eno ‘h to beat the mud until all the

lumps are gone and then slowly ad

P

/=

the required amount of emulsified

asphalt and et this mix in for a couple of minutes. The last thing to be

added is the straw, and as soon as this is fairly evenly scatt’ered through

the mass discharge it from the mixer into a wheelbarrow. Leaving the

straw to mix too long will make it tend to separate out by wrapping

around’ the paddles. When the straw is added the mixer may act like it

is overloaded; this is because the mass of mud clots together arid the

paddles encounter a lot more resistance.

. Prepare the casting s&ace by sprinkling it with a little sand or

straw tb prevent-the mud from sticking to it (which co&d cause cracks),

and dunk the mold in a tub of water, again for the purpose of preventing

sticking. Put the mold on the: casting surface and fill it with mud,

pressing it in with the hands and being sure to fill in the corners. Use a ’

trowel to strike the mud level with the top of the mold, and then lift <

the mold slowly Bnd evenly away from the newly created adobe brick. I’

A properly stiff niud w.ill stand with vertical or only slightly bulged

sides when the mold is removed. There is no reason to allow the mud

to set for a while in the mold before removing it.

’

/

The mold must be cleaned of remnants of clinging mud by dunking

in the tub of water before proceeding to make tfie next adobe.

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\.

Drying

Curing of Adobes _ -\-)

i

Side View

‘“i,,

_

. cLI

x.

-,.

Wetgbt to prevent wind

Shade cover

First Stage

3 or Y days

I

‘\\

surface made of scrap Iumbrr

‘\

Second

Stoqe

Cover removed & adobes

3 or L) days

% i

stood up on one

side when they are firm

.

Remove from castcng surface &

allow to dry in well-spaced rows.

Third statw

S or 6 weeks

$

r,

F.

---.-

-

+

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28

0 Drying and Curing

If newly made adobes do not have a chance to dry evenly they will .

tend to slump and crack, since wet .mud is not very stable. Cold foggy

weather is bad, and they must be protected from rain as well during

the first 3 or 4 days. Protection should be provided above the adobes but

not on the sides as the wind will help them dry. Once I covered a row

of adobes, top and sides, with a sheet ,of plastic to shield them from a

spring shower and I found the next day that they had all developed ,;

cracks and slumped sides because the plastic had kept all moisture

from escaping.

Another time, I lost n day’s production because I tried

shading them with roofing felt laid directly on top of the new adobes

and overlapping onto the ground; the result was the same as with the

plastic. Shade and protect, but don’t stifle.

Your bricks may dry perfectly under such ideal weather as- mild -

spring days, but a spell of hot, dry, windy days may cause widespread

cracking in r@w bricks no matter what you do. Bur ap sacks can be hung

over the edges of the shade providers to protect th bricks from dry

winds.

7

,

When bricks crack in the drying process it is. of en

center, but that is no loss ‘as many partial bricks are

i

directly in the

eeded in building.

Once I decided to groove the tops of some

of

my new bricks in

order that the mortar would have a better bond w/ en they were laid

up- in a wall. The next day, I found that thosef surface grooves

had

turned to cracks which, extended clear through the bricks.

cd-

As soon as your t&cks have dried for 3 or 4-days you should then

stand them up on one side .so that the drying will be more rapid and

even. Shade providers probably won’t be needed beyond this point.

About 6 weeks of drying in the, sun is long enough to get the moisture

content down to the required max imtim of 4.0%~ and then the bricks

can be stacked in rows several high to get them out of. the way. Stack

the bricks where they won’t interfere with future construction or

traffic.

\

\

Molds not in use can be kept in a barrel of water to prevent them

from drying out and beginning to part at the joints, or warp.

Personal experience with daily rates of adobe production showed

that I could make a max imum of about 70 of the 4X71/2X16 inch adobes,

oi 35 of the 4X12:X18

inch adobes in 8 or 9 hours of continuous hard

.

work. Often I could not achieve th is level of production because there

were bricks to be stacked, dirt to be excavated, etc. My maximum level

of production added up to about one ton of adobes ger man per day, ,:r

and this weight had. to be handled several times in the process of turn;”

ing undisturbed soil into a stack. of cured bricks.

,

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Discharging mud from the plaster mixer. Its gasoline engine is enclosed. This ma-

chine sits by your excavation site.

c

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Filling the mold. Note the inside of this mold is lined with tin. The casting surface

is made froni scrap plywood supported by 2x4’s.

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Working the mud into the corners o f the mold. You can see the iron corner brace

I

screwed’to the mold.

‘8

.

3

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Using a trowel to strike the mud level with the top of the mold.

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Washing the mold . If you ;don’t, the corners of the next brick will tear off on mud

left from the last one.

*

.

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- 1

Drying bricks where they lay cast, for the first three or four days.

f.‘

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Adding a shade cover.

.

c

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8’

.

--__

---------

.

Drying bricks on edge.,

i.

i

/

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.

6~lLDING

ADOBE BRICK

..”

.

‘.

:

I ’

L

1

_._---

__--

-

_

.

4. -i

/

.

-

. .

..

.

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.. _<

..-

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42 (originally a gift of Andrew Carnegie) as I was standing in front of the .

shelves of books on home construction and I saw one about how to build

an adobe home. From that moment on I knew what I was going to do,

and my first step was to check the book out and begin to read.

I didn’t know it’at the time, but this old handbook on adobe con-

struction followed standards which were not up to those set by the

Uniform Building Code, and it was several months before I even knew

that there was such a thing, as the U.B.C. After going through several

31

references on adobe I decided to go to the County Building Inspection

1 D.

epartment to see just what regulations they had’ about the subject;

’ there, I was told that the county would ‘approve my house plans if I

,I

could get an engineer or architect to approve them.

.

Not having any plans, I submitted a sketch of the floor plan that I

had in mind to an architect and asked him what he would charge to

draw up a set. He said that he would’ charge me a minimum of $1,800

for drawing up the plans and witching over the construction, and that

he would have t,o consult with other architects and e

gineers on various

details, which would add to the cost. My reaction was to decide to

make a downpayment on a building site and to begin the task of making

adobes; in the evenings and during the winter months I could continue ’

gathering information with the objective of making.my own plans.

Shortly afterward, one day in the late spring, we selected a site con-.

J sisting of an acre and a half of decrepit old apple and pear trees. The

*

nearby homes were of good quality, the ground water was potable, and

the site was level enough to simplify foundation design, yet with enough

_./_

slope to provide good drainage.

As a geologist? I could see that it was

about as safe an area as possible for minimiz ing the danger of earthquake

damage, for it was not on or adjacent to an active fault, and the ground

was weathe;sed rock in I;lace and not unconsolidated alluvium-.

Unconsolidated alluvium is recent sediment deposited in valleys,

lakes or bays by streams, and as it has never been bu$ied very deeply it

still has some settling to do if2 load is put on it. This tendency to settle

causes problems in foundation cl-,- so-sttch areas should be

.

avoided by heavy structures.

Also, tn areas subject to earthquakes

alluvium tends to. mtignify the vibrations caused by earthquakes, which

increases the probability of damage to structures built on it.

The grass was green, the lupines were in bloom, the sun was warm,

and it was time to get started making> adobes.

Usable information on planning-and construction detail came from

many sources:

) ; 1. The Univers ity of California at Berkeley s&s sets of plans for

i

adobe homes for very cheap prices. Write to:

”

Lc)no t&JT

-.

(w)‘; 6+ :+f)

. :G

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.C

Agricultural Publications

207 University Hall

University of California

Berkeley,, California 94720

” 43

- 2. Hans Sumph Co., ‘which makes adobe bricks, has construction

information and ,diagrams available for no charge. The address

is :

40101 Avenue 10

/

Fresno, California 93726

3. Wilson, J. Douglas, Practical Hot~se Cwpentry, McGraw-Hill,

1957.

‘4. County building inspectors-a very good source.

5. The Uniform Building, Electrical; and Plumbing Codes.

6. Richter, HP., “Wiring Simplified”, Park Publishing, Inc.

7. Building supply companies.

8. Friends who are building contractors or who work in the build-

ing trades.

9. Owners of adobe homes.

The floor plan that I finally worked out was for$an,L-shaped.house

with a living wing and a sleeping win,.

0 The L was positioned so that the

patio and the porch were shielded from the prevailing southwest wind

and given a sunny southeast exposure.

v;

.

There are several methods of approved adobe construction, but the

-”

one appealing to m

r

taste was that called “16 inch solid bearing wall”.

This is more traditional looking than the more popular “post and beam”

constrg:etion with 7% inch walls, .and it looked to me like it required

less engineering.-A bearing wall is one which supports any weight other

than its own, and any adobe bearing wall must be at least 16 inches _

thick. Height of adobe bearing walls can be a maximum of 10 times

the thickness. Adobe homes can be no more than one story high. No

.-

opening in an adobe bearing wal1 can be over 4 feet wide and keep

openings at least 3 feet from corners. Consult the Uniform Building

Code for details. ,

4

The information available from Ha?ns Sumph Co. covers “steel

frame” adobe construction, which uses a hidden framework of steel

pipe to take all of the structural stress and strain. “Post and beam” con-

struction uses an exposed -framework of 71/z inch timbers that serves the

same purpose as the steel pipe; the adobes merely fill in between the

timbers.

When I considered what I wanted, I chose to design toward the end

of having a home with which I would be completely satisfied when we

were finished. The floorplan included 3 bedrooms, 2’baths, an office, a

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‘A inch bolts 3 feet

2 inch bu 8 inch O. F.

:,

on center.

Concrete bond beam.

all +a’tc.

2;nch b, 8 irich

Redwood.

i inch

mortar

tn center.

iOi?lt

‘1 hor\zontaI 3/6

VAUII

% inch rebar 30

sinches on cente

Hook ends.

Adobes

Solid Wa

II

I I I

'onstruction

inch rebars every

course.

Details

Drill 2 inch hoi

for vertical re

12 Inch Nonbearing

Y Wall

big combined living room and dining room, a kitchen, and a service

room. The porch was a’ hearty 60 feet long and 7 feet wide. Useable

floor space, exclusive of the porch and areas occupied by walls, amounts

to about 1450 square feet. Each room was considered on the basis of

what it would be used for and given correspondingly adequate dimen-

sions. Four by four inch porch posts would have served to support the

porch roof, but 8 X 8 inch posts were more in character with the massive

aspect of the rest of the house. s/s inch glywood sheeting.on the roof

was good enough for structural strength, but I added 2 X 8 inch T & G

pine for visual effect with the exposed beam framing members, and for

insulation. Aluminum window frames are cheap and easy to install, but

they look out of place in an adobe home so I bought lumber screws and

.’

glue and made my own swing-dut double casement windows.

To make them is not difficult. Buy sash stock at a sash and door

shop, cut the pieces at a 45” angle in a miter box, and put them together

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with exterior wood glue and a couple of iong wood screws at each joint.

Use clamps to hold them together until the glue dries. Allow an eighth

of an inch clearance all the way around to’avoid problems with swelling

in wet weather. 1 inch by S inch IT-Rustic pine was used to cover the

gable ends and the 4 wood partition walls in the home. All this kept us

broke, but now there are’no regrets.

Making the adobes took our spare time for 2 years during the

months of late spring, summer,

and early fall, and when that was

finished the required tests were made (the commercial testing lab-

oratory in San Francisco that did the work told.me when f called for

the results

that -all the test bricks’had fail;d the test for modulus of -

rupture, but it t Ll

ned out that they had misplaced a decimal point )

Adobes are made commercially in some’ places with machinery

capable of producing several thousand per day. To purchase the num-

ber of adobes that we made would have cost us about $3,000.

.

Shortly after winding up our adobe-making I took my nearly com-

pleted house plans to an engineer to get his analysis of their structural

competence and so he could recomniend properF*beam sizes and spacing,

-A

_

the amount of reinforcing steel needed, the types of beam fasteners, and

’

*

Lintel over a casement window, seen from the inside looking out. Note concrete,

window $11.

^

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i

46

.-

1

.

I

-

-. ..,.. -_

bolr data. The formula followed for figuring the proper amount of

reinforcing steel to put in our adobe walls was: “a minimum of 0.002 of

the gross cross-sectional area, not more than 2/3 of which may be in

either direction.” The bill for the ,engineering calculations, .which- are

in the Appendix of this book, came to $110, which.7 was quite happy

about .

In drawing the plans, I followed the same drafting system as used in

some plans that I bought f&m the University of California. The plans

were drawn on 24 X 36 inch tracing paper .so blueprint copies could be

made’casily and cheaply. I used the 1 to 30.ele on iny engineer’s ruler

and counted each division as one inch.

Upon approval by ,-the Sonoma County Building Permit Office of

these plans, the work of building the house began. By. this time, we had

finished paying for the land and could apply our money toward buying

construction materials.

.

,

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47

i:. ,

. THE FOUNDATIOti ’

Foundations for adobe buildings are more massive than those of

.

wooden houses as there is more w.eight to support.

Depth of the founda-

tioh is dependent on soil conditions and an engineer should be consulted

I-

? -

on the matter. Foundation footings’must extend beyond the foundation

wall on each side by 50% of the width of the wall.

Adobe ‘house. builders in p Mexico ’ construct foundations by first

digging a shalloti trench and then laying large ro&@ it. The rock work

..c‘

is carried up to about 10 inches above the surface of the ground and

then the laying +kf th.e adobe bricks begins. By keeping the base of the

+ adobe brick section of the Fall well above ground level the underminingI

effect of splashing rainwater that drips from the eaves is avoided.

As our building site wasa fairly level and the ground was solid, /”

fhere &eie no particular problems in foundation desigq ,Such a book as”

T’ructicct~ Ho&e Curpefitry does. a good job of, instru&ing you in

how

to lay’out and build.foundation forms.

./

Our foundation trenches. were dug v&h pick and shovel in- the

”

heat of the. summer, resulting in our moving about 80 ton.G”bf, dirt and

I

wearing off one inch of blade’on my favori t; shovel (some 40’0 tons of

- ‘- , dirt had been’ moved by pick and shovel by the time all phases of con-

,

.

struction were finished): TQ save on lumber, I .made the trenches thg

exact width of the foundation footing; to mark the top of the footing,

nails were 8tuc.k into the side of the trench.

% TWO* 5% %bars w.ere positioned” in the trench atop pieces of brick

and then’ready-mix concretf was poured in. If a fireplace is wante,d, a 12

c,

inch deep-reinforced co.ncrete’pad for it must be poured, with the rebar

_jp*

’ tied into the foundation.

,:

It took about 3 months from the time that,, I started digging the

: ,

* c

I

7;.

.>

.

%.

r.

I-i _I

_ .

,&J* . o

1 ,

.

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48

foundation trenches to the time the last of the concrete was poured.

Ready-mix concrete, which is brought to the site in concrete-mixer trucks,

costs about $20 per cubic yard. ‘You can’t m ix your own that cheap.

As the pouring of the foundation footing was finished, pieces of 2 X 4.

,inch lumber were set in the fresh conctete and then removed when the

concrete was firm. This provided a key to later help bond the foundation

wall to the foundation footing. To further anchor the two together, 2 foot

long pieces of 5% rebar were stuck into the fresh concrete at 30 inch

intervals. See my diagram of Adobe Solid Wall Construction for details.

0 Next, forms for the foundation wall were set up and more readymix

was poured. To provide for the vertical 5% inch rebar needed for the

adobe wall, I used a measuring tape and pieces of 1 X 2. inch lumber

with holes in them to position the rebars and hold them in place while

pouring. Electrical outlet boxes and connecting conduit were wired to

the insides of the forms where necessary, it being more difficult to cut

outlets in adobe walls. Be careful to plug all outlet box screw holes with

something to keep the concrete out.

0

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“49

3-Y

r

LAYING ADOBE BRICKS

,

The following equipment is needed for laying adobe bricks up into.

’ ‘ ‘Adobe walls:

_ -~

~~~.-.* -*ms iew

e-@keepsh~s vertical---

2. A 2 foot level for leveling individual adobes as they are laid.

3. A ball of nylon string for use as guides to keep the walls level

and vertical.

4. A wheelbarrow and a hoe for mixing mortar.

5. A co’inbination rebar cutter and bender.

6. Gloves, thin, for freedom of movement.

.I

: 7. A brace and bits, or an electric drill with a masonry bit, for

drilling holes in adobes.

‘.

8. Wire brush for cleaning rebar.

-9. Shovel.

-----___

10. Various buckets.

11. Brick Snlitter.

?

The first step is to clean the top of the founda ion

parallel % inch rebars about 3 inches in from the

d

and lay 2

edge .

Rebar should

be free of material-such as dirt, loose rust scale, oil, etc.

t ensure a good

7

’

bond with the mortar.

The,next step is to.mix up a batch of mortar in your wheelbarrow: -

Mortar is mixed in the proportion of 1 part Portland Cement to 2%

parts clean sharp sand. As ‘the-mortar is required to be waterproof,

emulsified asphalt must be added to the mixture in the proportion of

1% gallons per sack of cement used. Start by shoveling in* the amount

of :sand and cement wanted and m@cing it in the dry state.Udd clean

water, -a little at a time, and mix with a hoe until a stiff but moist

~___

mixture is obtained (sloppy mortar will squeeze out from under- the

2

-.

7

.

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50

adobes and will not stay in the vertical joints). When the mortar is

the right consistancy, slowly add the emuls ified asphalt and mix

thoroughly. Use hot water on cold days for less trouble with the asphalt

and ‘to keep the hands feeling comfortably., warm. Do not use lime in

the mortar.

Mortar sets up fast, and I found it- best to mix up only a small

amount at one time (5 shovelfu ls of sand and 2 of cement). If delays

cause your mortar to begin to stiffen before it can be used, it is per-

missable to add a small’amount of water and mix to restore the right

consistency. -

The 120 tons of adobes in the walls of our home required about 30

tons of mortar.

Lay corner bricks first, but before doing so hammer in the nails

needed to anchor your string guides. It is easier to lay either the otitside

or the inside course of a 16 inch wall at one time, but not both together

as shifting mortar causes trouble. Wet the top of the foundation and

place some mortar on it. Spread the mortar out with your gloved hands

nsive

pointed mason’s trowels, but never used

them) until it looks fairly level and about 3~4 inch thick. Clean the

bottom of an adobe of loose dirt, wet it, set it on the mortar and slide

it back and forth a little so that the bottom is completely in contact with

mortar. Use your small level to see that-the tops of the corner adobes

are lever both lengthwise and crosswise, and also use it to be sure that

the outboard sides are in the same vertical plane’as the’ sides of the .

foundation. If adjustments..are needed, use sliding motions or taps with

your fist to move the adobe and then recheck with the level.

.

After the corner bricks have set long enough for ‘the mortar to

j ,

&y, it is time to place the string guides which help in laying the rest

of Jhe bricks in the course. Tie a nylon string to the base of the nail in

.the top of one corner brick and then dull it tight and tie it to “the base

Y

Top s&g guide

'/r inch

iece OF Lath,

l

Stde string guide

B

a

1

a

---

+

1

---- _---_---_.__

Lb= Nail

1

~[+ll---~[-(

UI

u

II

\’

4

~%>,

.’

=,

s

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I

‘<

;

.

2

s

.-

0

---I

n

L-M

?i”

01 bl

w

v,L

GA-

i. \

i

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5.2

of the nail in the top,of another‘corner brick; do the same with a string

for the nails in the sides of the bricks. Place a piece of lath under the

string in front of both top string guide nails to raise the string about 1/4

inch; hook a couple of bent nails or staples over the side string guide to

hold it out from the sides of the corner bricks ‘about l/s inch. These

string ‘guides now allow the laying of the adobes between t,he corner

bricks without anymore recourse to the level except to use it to level

the tops of the adobes -in the crosswise direction. By eye, keep the

adobes away from the string guides by the amount of clearance set with

the pieces of lath and ‘bent nails at the corner bricks. I used ‘individual

string guides for up. to 50 foot long stretches of wall, but I divided the

80 foot back wall into 40 foot sections to avoid complications from

sagging of the top string and wind movement of the side string.

As the wall gets high&$-use-the 6 foot level to keep the corner bricks

vertica l with the side of the foundation.

Lay adobes from the corners toward the centers of the walls, and

overlap them by 50% as much as possible. Fill the vertical joints with

mortar after completing a course. If you wish,. the adobes to project

in relief, then yo’u can rake the mortar joints back a half inch with your

fingers before ihe mortar hardens.

If a,space needs a less than full-size adobe you can make one with

your brick splitter and hammer. First, groove the adobe & the way

around with a nail, and then place the splitter at various places along

the groove and tap it with the hammer, hitting progressively har#ler until

the adobe splits along.,the groove. Adobes are homogeneous in structure

with no preferred cleavage planes, and so the tapping creates a plane

of weakness,

I

‘:

\

Where door or window openings are to occur, set vertical nailing

.

block frames of 2 X 4 inch Douglas Fir. These are for the purpose of

fastening door and window-frames. The nailing blocks are’recessed into

the wall by notching the: ends of the adobes, and they are fastened to

the wall by driving a couple..of 16 penny nails into the blocks at the

level of each horizontal joint and letting the nails protrude into the . *

space so they will be held by the-mortar.

4-

;/

.---

;.”

)%&&LITLT

he non&bearing adobe partition walls in the home

4 X 12 X 18 inch adobes’ and are 12 inches wide. HoIes must be di$led

in the adobes where the vertica l rebhrs do not correspond with vertical

joints. An electric drill with. a masonry bit would be the-easy way-to---

drill these holes, but I used a brace wi&a-3L4 inhmdebtEsTL wood

bits lasted for abou ZholesaEl’3hen they were shot. Holes were end

e

-large&to%- iameter o f 2 inches with a rasp.,

/--- .

The rate at which I laid adobes was a maximum of 60 per day of

..__’

-..

-_

-.- -_

. . __

_

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,: _.

----.L- -

eyi___.---

._._ ---_-~----____

--~_ ___

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. Scale

e II inther+

Notch &bar

to iit around

$-~fritien of;.2 n 12 inch :

I---“.,---.-.

win+ javn*. -==--I

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I

I

.

,.

: f;

,

the 4 X‘7Vt X 16, and 25 per day of the 4 X 12 X 18 inch&s. I ‘was slow

and careful, and the results were- good. *’

I

TWO electric light switch boxes had to be placed in the adobe walls.

This wti done by putting in the boxes and laying adobes -around them.

. A piece of conduit extended from‘ each box to the center mortar joint

’ I

in the wall and then upward to just above the top of where the bond.

beam tias to be.

-” --- _?

My scaffolding ,for working on the walls consisted of 55 gallon

‘,drums and planks. ~.

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---

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./-

-

-LINTELS, BOND BEAM, *AND, WALL PLATE

,’ f==y ’

“A Lintel is a horizontal architectural member span&g and usually

’ carrying the load above an opening,”

according to Webster’s Dictionary.

Lintels in old adobe homes were often made-of wood, but now they’

must be of reinforced concrete extending at least 20 inches beyond each

side of the opening. For details, see the engineering calculations in the

Appendix. ,-

I used 2 X 8 inch Redwood for the sides of the lintel forms, and after

the concrete set, these were left in place. The bottoms of the forms qver

the openings were of s/s inch plywood, CDX; held in place with clamps.

i So that the wood would remain fastened to the concrete, I drove nails

through the plywood into the interior of the forms, and from the inside

of the forms I drove nails part way into the Redwood.

A bond beam is a continuous layer of concrete which is poured

along the top of the adobe wall, thus tying together the vertical %s i&h

rebars which come up through the adobe walls from, the foundation.

Forms here were constructed in the same manner as for the lintels: Be-

fore pouring the concrete for the bond beam I had to position the bolts’

for the fastening of the wall plate and the-angle irons that wauld be

. . -.

_ holding the rafters and---h udr\nps

of plywood with holes drilled in them. Again, see the Aopendix for

, ‘...

details.

I

\ e

Concrete for lintels and bond beam was mixed by hand, using 1 hart

cement to 5 parts aggr.egate mix , Buckets were used to hoist up about. 15

tons of concrete ‘to the top of the .wrall. .The sand“and gravel aggregate _

mix came from a building materials supply company. Pieces of 2 X 10

‘inch Douglas Fir were bolted to the bond beam for the wall plate. See

my engineer’s calculations in the Appendix for details.

, ,

- -

‘ -

L.

‘ i

4

.-

_ ._____ ~ ____ _ .~~_~ ~~ - --

-- .

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i

THE ROOF

Irr,

rc7.

’ ‘:\

1

The first step in constructing the roof was to buy in advance the

Douglas Fir beams needed for the rafters, joists, ridge beam;, and porch

p&s and headers. These I wanted in the rough, and ‘they (had to be

cut especially at a mil l. When they were ,delivered,-“we spent 2 days

-stacking, spacing and shading them so they would dry;:without warping

and cracking. Some warped and cracked anyway.

-

-

All of the angle iron and washers for- the roof3 fasteners had to be

made up in a machine shop. For clearance, the bolt holes in the angle

‘.

irons were made 9/16 inch in diameter.

I had thought of hiring a carpenter to help with the framing tf the

roof,. but when the time came to begin there was no money.

;l When the wall plate and the angle irons had been bolted down, I

began the task of getting the beams up onto the top of the wall. This

took several days.’ To get the long heavy joists to the top o f the wall I

would set them on the top of a 55 gallon drum placed near an outside

. corner of th$ wall and then raise one end by pushing down on the other

end. When the high end of the beam was higher than the top of the wall

I would then pivot it on the drum and swing it, over -and down to the

-w

all. Now, I could heave on the,lower end of the beam

uhtil it

---

nt up

%

nd over to fall across the interior ‘angle of the corner.

Spaci ’ of th4 X 6 inch raft& and joists was set 4 feet on center;

wexcept in th living room and- the dining room where’ the joists were\

6 X 8 inch beams and set 8 feet‘on center. First to be set in position and

drilled were the $ists. Next, pieces of 4 X 4 inch lumber were set on

sqme of the joists along the. center line of the roof and the ridge beam0

was set on these and nailed and braced temporarily.

--.,P

, -

To set the rafters, I first cut the ridge beam end of a rafter to the’

” *, .

_ =

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WaM and roof construction. Note lintels over winMows on the left, door opening on

;

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with two 16 penny nails at each bearing.point on a rafter, and staggering

57

(he joints. It was sometimes difficult to get the T & G to fit tightly to-

gether, and so I would have to na;l a block of wood to the board that

was already nailed down and use a clamp, one hook on the ridge beam

side of the block and one hook on the lower edge of the loose board, to

draw them together.

For’ structural strength, 3/s inch plywood ‘yas nailed over the T.& G.

I used the type called CDX, which is made with exterior type glue so

the weather won’t hurt it. Joints were staggered 50%.

Roof beams were all stained before the sheeting was put on, and

I

the T & G was stained before it was put in place. a

Positioning of holes for vent p ipes should be done with a plumb bob,

as I found that dropping a rock, which I tried f irst, is not very accurate.

Porch posts were spaced 12 feet on center to\,provide plenty of room

for slinging hammocks.

‘\

The final covering on the roof was Redwood shakes, nailed to 1 X 4

inch Douglas Fir nailing strips. In the Uniform B&ding Code there is

a section on specifications for shake and shingle roofA

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58

PLUMBING <

There are no great mysteries or hard-to-acquire, skills assoeiated with

the installation of a plumbing system in a home. Excep.t for one day of

my father’s time, I gs able to do all of my own

plum Ll*

g;. everything

works.

The best way to find out what to do is to study the Uniform Plumb-

ing Code an& your local county building ordinances. Inform.ation on

-how to do it can come from asking-questions of the building supply

TpeoPle from whom the materials are bought, and I got some help f,rom

$ a well-illustrated do-it-yourself plumbing book (which was not up -to

’ Code) from Sears Roebuck. When in doubt, ask your building inspector.

Our water supply is from a well. From the well, a trench was dug

250 feet to the house and plastic pipe, called PVC, was laid in it along-

side the wires needed to supply electricity to the pump. PVC is cheaper

than metal pipe and will not corrode. -It can be cu

with a hacksaw, and

it is put together with a special glue, and slip-on

fi

t

tings.

As the distance

from well to house was so ,great, 1 r/2 inch pipe was used to avoid a

? ’

4 pressure drop. A couple of inches of sand ‘were put under the pipe to

’ minimize the chance of differential settling causing the pipe’ to break

when the trench was filled in.

d

* About 2 feet outside the house a. tee- went on the line to pro&de

branch lines to outside hose bibs for the garden. Then;, an adapter went

on the line so I could change’over to %4 nch copper pipe.*Before entering

the house; a gate shut-off valve w,as put on the line so that the house

”

water could be shut off in case of possible plumbing disasters.

All ,of the water suppIy lines in the house“aie: copper. There are

~--

sdifferent types of copper pipe, determined by the thickness of the’wall of

the pipe, to be used in different cjrcumstances:‘Y&he book from Sears

*

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P

~ -----.-- --

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gave good instructions on how to solder the pipe ‘and the Wings to- II-$$

gether,$.and the only trouble- that had yas that ‘at first I would get the

fittings t*& hot and the solder would not adhere to the-copper, and once --’ .

L copper has bee6 overheated it will never be solderable. The Sears’ book

lists the materia ls and-the tools needed to install the various fypes of

i J .

cold water ‘pipe has l&inch- branch lines to the ‘.

kitchen, service room, and bathro&?” fixtures. The, various sinks, wash- . -

basins- and toilets are connected to the ‘v2 inch branch lines by, means of ’

I

3/g inch flexible copper tubing. This tubing may be bent with ,a regular’ -,

e

_ tubing bender of, by filling it- with dry sand, by bending it by hand.

Shutoff valves connect thetipipej and ‘the fubing.

Copper pipe should’ never corn

se in contact with other metals as

Pelectrolysis will destroy ,&pipe.

_

-_: At the. hot water heater; a check valve and a shut+off /valve were 1’

I’

*_

’ installed on the &coming cold water line. A water pressure relief valve

was installed on the hot wate r line outlet and itsdrain’was extended to .*’ P

outside, the. house. Flexible tubing (with attached fittings yas* used Pto /’

connect the heater to the water p@s. Hot’ water lties are l/2 inch

L .

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cbpper pipe:’

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/’

Hot and cold Gater lines for thejwashing machine have hose bibs

/

1 -:

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on the end&

To learn about installing ,toilets Laskkd &est&& of the owner 6f

_,

-* he stor

i

where I bought them. The process, is simple:

.’

,l,. Slip toilet ring over end of toilet bepd. /il’ ’ - &-

D x’ 2. /Caulk lower portion.,of gap between ‘inside of toilet ring and Out-

side’aftoilet-bend with tow.

e

+.

. 3. Fill’remainder of gap with molten lead. ;

82

I

4,--Press a, wax gasket around the toilet bowl outlet. ’

9

5, Bolt toilet to toilet ring, tightening the nuts only finger tight to

*avoid cracking the bowl. * ,% s

- ,,’

I-

.

Drain .lines are of hubless

pipe held ‘together with fjexible i

plastic sle’eves and stainless stee

amps. The main drain is 4 inch pipe .’

B

-

andthe feeder drains are 2 inch,. The minimum allowable grade is $$

se

inch~r?o%-Arenich~typepipectrtter wasused to cut the pipe. .

~

Vent pipes are used to get rid of gas that forms in the drain lines; .-.*

They .may be of hubless cast-iron pipe, although I used-galvanized pipe. -

“:,

Here is a check list. of some of the things to ‘be remembered;

.A

1’

1. House drain must be 3 inches minimum for 2 toilets.

--

.L- 2.1 All horizontall drain lines-.reauire cleanouts; which must be

a&&sable and have’l.8 inch’& minimum- clearance in front.

._ _ v__

- .i, q

..i: .

X Use “Comb

in&on Y” and “r/s” bends ,at intersections of hori:‘. ’

i e

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60

zontal and vertical drain lines.

4. Keep traps as close to fixtures as possible.

5. Install sanitary tees at fixture inlets to drain lines.

6. Approved type of panlor shower intercepter subdrain and 2 inch

trap required for shower.

--- -.

7. Main vent same size as house drain.

,8. Maximum distance from fixture trap to vent is 24 inches.

9. Intersections of,vertical fixture vents and horizontal vent lines

must be at least 6 inches above rim of fixtures served.,

_I’

10. Galvanized iron pine 6 inches minimum cle?rance above ground

or concrete slab floor,

A..

11. Consult county plumbing ordinance for maximum number of

fixtures on each drain or vent line. ;.

No sewe,r.lines exist in our area, and so a septic tank system had to

be iY&alled to treat and disbose of the sewage from the main house

----~-----drain. Information on how to laydout. this system and make the necesd

sary @?calation test was obtained from the county health department

I ‘*

(see Appendix for dtiails). .We did all of the shovel work ourselves,

some 140 t,ons of dirt moving. A ready-made concrete septic tank and

distribution boxes were bought from a dealer; who-brought the tank out

on a truck with a boom and lowered it directly into the hole with no

2

,$

-trouble. I had considered makipg rni own tank, but the time and money

’ -.

involved favored buying one. The 40 yards of drain rock needed, cost-

. irig $3 per yard, delivered, came from a nearby quarry. See the diagram

8.

- in the Appendix for lay+outs of typical septic tank systems.

. I was intrigued to learn from some of my reading on Mesopotamian

ar’chaeology that 4,000 years ago those people used vertica l leach lines

for disposal of sewage. These consisted of shafts sunk down for several

+-~----

tens of feet in which were placed strings of perforated fired clay pipe. ‘-

Broken pottery was filled in around the,pipe to act as drain rock.

s

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61

ELECTRIC “WIRING

Wiring a home is more involved than doing the plumbing, but all

of the elements are . basically simple. By studying the book Wiring

Simplified, which f 11ows the National Electrical Code, I learned all

that I had to know about laying-out circuits and wiring switches and

outlets. Another book that helped, and one that has many good illustra-

tions, is the Sears Roebuck book Simplified glectric Wiring Handbook,

although it does not follow the Code in all respects. The Sears book has

an illustrated list of the tools needed and describes their uses; When in

doubt, consult your building inspector.

To start my electrical system, I began by studying the ab ve books

dand laying-out a wiring diagram on a floor plan of the housp. The posi-

’ tions of switches and outlets were selected and then theyfiere divided

into various circuits. Special circuits for the stove, dryer, and the washing

machine were drawn in. I learned about the typ,es of wiring and the

conditions under which they may be used. There are tables which de-

scribe the sizes of wire which must be used, and the capacities of conduit,

.--~~-~_

switch boxes and outlet boxes forn&@bers of wires accordmgto size. The

information began to see@ n.

Conduit embedded in the concrete foundation was used to bring

‘wires to the base o’utlets in the sections of adobe wall. Rpmex was used

in the wooden partition walls and along the tops of th&adobe walls and ’

joist beams. Romex does not have to be c&L%&d if it is more than 8

feet above floor level.

I

-he only tools needed beyond my carpenter’s tools were a conduit ~~- -

^ bender and a tool for cutting and stripping wire.

‘*

_.

The actual wiring involved onIy about 4 different hook-ups: It‘took

time to become familiar with

them,

but I did them all correctly. Twist-

*_

_--

2

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$4

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..--..- .-

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62

on solderless connectors make the connection of wires a simple thing.

Clip-on wire clamps ground the ground wires to the switch and outlet

boxes. Circuit breakers were used in place. of fuses in the main panel.

When it came time to check my ciFcuits, I taped the ends of e&h

circuit together at the main panel and then used a friend’s ampmeter to

check continuity by making contact at the contact sarews of each outlet.

-.-

,’

.I’

It wasn’t until all of the wiring was completed that the power com-

.

pany brought in power to the house. Not wanting. power and telephone

lines visible around the house, I dug a 220 foot long trench to the nearest

Dower nole and had that section laid underground.

--

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d

d

.Probably the most important asset t

ospective adobe. home-

builder can have is the ability to read ‘and

conviction that ,there is @ways a way to

accomp

more important than previous experience in any of the buildi

In all phases of planning and building it is necessary to find

outdan

under&-id what your county building inspector requires; to consider the

types and the merits of materia ls that can be used; and to find.out about

’

and use the proper tools.

Our home cost us about $6.50 per square foot to build, ,exclu-

siye of land and water supply costs. I would estimate that a rectang-

ular-shaped 2 bedroom home with about 1,000 square feet of’useable

floorspace could be built for about $7,000 in materials. ‘SVith the out-

side walls built in the 16 inch,solid bearing wall method .and some 12

inch wide, adobe partition walls, about 4,OOD adobe~would-be-needed.

_c___

ScrutinvCnt rental businesses to see what they

.

It is not necessary to have electric power on the building site. All

of our digging, sawing-and drilling were done by hand. Several times I

had to drill 12 inch holes in the concrete- foundation for water pipes,

and this was done with a star bit and a 2% pound hammer.

w.. . . *

.-

e are elasticiling a shower or a sink counter is not difficult. Ther _

adhesives that permit tiles -to be gl.u.ed directly onto a plywood\ backing.’

We used a mottled green Japanese ceramic ..rile with ..wavey edges and

grouted the joints with gray mortar. Instructions and the simple tools

needed can be obtained where one buys, the tile and the adhesive.

Latex base paints are recommended if adobe walls are to be painted.

Oil base paints will not do as the &I penetrates’ the bricks and bonds

‘-

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The 5Isty-foot long porch, s-t111 ncomplete.

Sow casement windows nearly flush

lvith the wall, lm trls abovtz each.

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with the,asphalt. If the natural color is war&d, Gt-something is needed

65

-to’.keep the adobes from shedding dust when touched then used a clear

water seal such as Thompson’s.

We were able to opera,te on a pay-as-you-go basis with regard to

financing. If you wish-to test the reaction of the upholders

the estab-

lishment when, confronted with the true initiative and pioneer spirit

that they claim to admire and nourish, then just try talking with your

local lending institution officia ls; y&r’11 find out that they mean the

pioneers who are listed in Dun & Rradstreet. It is gratifying to be able

to do without them.

If you are &nning to buy an unimproved lot in the country, it

is recommended that a thorough investigation be made concerning such +

items as those listed below. Your smiling real estate salesman may neglect

to furnish accurate information.

1. Soil percolation and septic tank system sites. Many counties re-

quire proof of+good soil percolation for disposal of septic tank eff luent

before they will issue a building permit. Usually, a lot -must be at least *

an acre in size. to allow for a home site, a well, and a septic tank leach

field.

2. Cost of drilling a well, the probability of finding water, and the

0 ’

iqualitpof that water.

*

h 3. Co&+bring@g in electricity.

4. Access to the.& ._

5. Boundaries. The corner posts shown to you may’not be accurate-

ly located if a survey has not been made. The title insurance that I

have seen (mine) does not insure against such mishaps.

6. Zoning and community development masterplans.-- ~__ ~__ --- -

It is best to reckon on doing at least 95%. of the work yourself bed

cause there is such a great amount of. it that occasional volunteering by

friends and relatives doesn’t whittle off very much, no matter how much

it is appreciated. Resides some general labor, as you go along you can

expect to receive some helpful advice (a hod carrier taught me ‘how to

set string guides), some skilled work (a retired window glqr put all the

glass in my window frames), and various gifts and loans of tools and

materials. It all helps, and*at least it is nice to have company.

We have been living in our adobe home for 6 months now and

there are still portions of it that are not yet finished. In building an

adobe, it seems natural for the builder to want tomake everything him-

* self. To cover the concrete slab floors, I plan to make some 1,400 big

.- -

red tiles of the type used in the early California missions. This will take

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-:--

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”

n

APPENDICES

2 . _-

=-

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7.

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n

71

Nearly.:, 30 years ago I live+ for a few months in -one of four adobe

duplex units jn the desert ai Thermal, California. At the time the

extraordinary feel&g of comfort and well-being I experiinced there

seemed to be due to their’ good construction. Over the years, I came

\

to realize that there was a more subtle and complex explanation

which included the tender loving care supplied by the young couple

who were builder-owner-tenant-caretakers, and some other ingredient

adobe seems to radiate just by deing adobe.

Gene Boudreau .and I- became good friends as soon as we met

about twelv,? years ago, and he worked. for’me a short time before

his first trip to Mexico, where he met his wife, Sylvia. I saw them for ,

the first -time in several years .recently, after they had raised the walls _

”

1

on this house, and I helped them celebrate the event. *

I have thought, about building. my own from- time to time, and

have kept 3 file of information about adobe construction, but I was

_.~ ~ ~

never able to find a bbok which told me whe&& d to know:

The urge is getting stronger now, and with Gene’s b&k..@ my library,

I expect to &gate the opportunity to:.)actually start as, soo;i‘-as possible.

If you live close enough *to make us& of his personal services, as I vill,

I‘ would certainIy recommend it.

I believe Gene has treated the engineering and building code.

aspects very well in this book, but the requirements will vary over a

wide range for readers in different “areas. Less conservative construc-

c

tion has been built by lay~men long ago which has lasted many years.

If one,: follows the principles qutlined in the first paragraph of the ’

pr

sectiqn on “Loose Ends”,

I’ am sure any problems in this area will

_-- --

be #lequately resolved. N&w.

get started

.‘,

*R; Wm. Rollins

-+ d

. ,x

Registered Civi l Engineer SS55, Californiu ’

’ D ‘. -

A llgtls t 197 1.

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-

‘5

E

2

72

. ,

UNIFORM BUILDING CODE

REQUIREMENTS FOR ADOBE BRICKS ’

.

Many counties base their building codes on the,Uniform Building

.

Code, in which are included certain standards set for “unburned clay

1

brick”, meaning adobe bricks, and their use. Anyone planning0 to make

adobes should consult,with his local county’building permit office to

see if they require anything-in the way of standards beyond those set by n

’ the Uniform Building Code. If your county has not adop;ed the Uniform

5 Building:C o

d

e and has no oth%er standards then it is still a. good practice

0 to conform with the U.B.C. Copies can be found in libraries and book

. _

stores.

6 The follotiing is quoted from Uniform Building Cod